#3312 Roblox Voxel Builder

#3312 Roblox Voxel Builder

#3312 Provide a Roblox script to enable a player to build voxel-based structures

Below is a clean, ASCII-only implementation of a grid-snapped voxel builder that lets players click to place blocks in real time.

It uses one RemoteEvent, one server Script, and one client LocalScript.

---

1. One-time setup in Studio

Location	Object	Notes
ReplicatedStorage	Folder - “VoxelAssets”	Holds shared templates
└─ VoxelAssets	Part - “Voxel”	Size 4 × 4 × 4, Anchored = false, CanCollide = true, BrickColor as you like
ReplicatedStorage	RemoteEvent - “PlaceVoxelEvent”	Used to ask the server to place a block
ServerScriptService	Script - “PlaceVoxelHandler”	Paste the server code below
StarterPlayer ▸ StarterPlayerScripts	LocalScript - “VoxelBuilderClient”	Paste the client code below

Grid size is 4 studs everywhere. Change SIZE in both scripts if you want a different voxel size.

---

2. Server-side script

ServerScriptService/PlaceVoxelHandler

-- PlaceVoxelHandler (server)
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local event = ReplicatedStorage:WaitForChild("PlaceVoxelEvent")

local voxelTemplate = ReplicatedStorage:WaitForChild("VoxelAssets"):WaitForChild("Voxel")
local SIZE = 4                     -- grid size in studs
local MAX_HEIGHT = 200             -- build height limit

-- Snap a Vector3 to the grid
local function snapToGrid(v)
    return Vector3.new(
        math.floor(v.X / SIZE + 0.5) * SIZE,
        math.floor(v.Y / SIZE + 0.5) * SIZE,
        math.floor(v.Z / SIZE + 0.5) * SIZE
    )
end

-- Called when a client wants to place a voxel
event.OnServerEvent:Connect(function(player, rawPos)
    if not rawPos or rawPos.Magnitude > 1e5 then return end
    if rawPos.Y > MAX_HEIGHT or rawPos.Y < -SIZE then return end

    local pos = snapToGrid(rawPos)

    -- Simple collision check: is there already a part at this CFrame?
    local region = Region3.new(
        pos - Vector3.new(SIZE/2, SIZE/2, SIZE/2),
        pos + Vector3.new(SIZE/2, SIZE/2, SIZE/2)
    )
    local parts = workspace:FindPartsInRegion3(region, nil, 1)
    if #parts > 0 then return end  -- space is occupied

    -- Place the voxel
    local voxel = voxelTemplate:Clone()
    voxel.CFrame = CFrame.new(pos)
    voxel.Parent = workspace
end)

---

3. Client-side script

StarterPlayerScripts/VoxelBuilderClient

-- VoxelBuilderClient (local)
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local UserInputService = game:GetService("UserInputService")
local RunService = game:GetService("RunService")

local player = Players.LocalPlayer
local mouse = player:GetMouse()

local event = ReplicatedStorage:WaitForChild("PlaceVoxelEvent")
local voxelTemplate = ReplicatedStorage:WaitForChild("VoxelAssets"):WaitForChild("Voxel")

local SIZE = 4   -- must match server

-- Ghost preview block
local preview = voxelTemplate:Clone()
preview.Transparency = 0.5
preview.CanCollide = false
preview.Anchored = true
preview.Material = Enum.Material.ForceField
preview.Parent = workspace

-- Snap helper
local function snap(v)
    return Vector3.new(
        math.floor(v.X / SIZE + 0.5) * SIZE,
        math.floor(v.Y / SIZE + 0.5) * SIZE,
        math.floor(v.Z / SIZE + 0.5) * SIZE
    )
end

-- Update the ghost every frame
RunService.RenderStepped:Connect(function()
    local ray = Ray.new(mouse.UnitRay.Origin, mouse.UnitRay.Direction * 512)
    local hit, pos = workspace:FindPartOnRay(ray, player.Character)
    if pos then
        preview.Position = snap(pos)
    end
end)

-- Left-click to place
mouse.Button1Down:Connect(function()
    event:FireServer(preview.Position)
end)

---

How it works

1. Client ray-casts from the player’s camera; the hit point is snapped to the nearest 4-stud grid, and a semi-transparent preview cube is moved there every frame.

2. When the player left-clicks, the client fires PlaceVoxelEvent with the snapped position.

3. Server validates the position, checks that no part already occupies that grid cell, and then clones the voxel template into workspace.

---

Extensions you can add

• Right-click to delete – send a different RemoteEvent that destroys the targeted voxel on the server.

• Per-player block limits or permissions.

• Different materials/colors – pass a color or ID in the RemoteEvent arguments.

• Saving/loading – serialize all voxels’ positions to DataStore when a player leaves.

This skeleton keeps the client authoritative for aiming but the server authoritative for actual placement, preventing exploits while giving responsive building.

From <https://chatgpt.com/>  ChatGPT o3